public class Main {
    public static boolean isAdmin(String userId){
    return userId.toLowerCase()=="admin";
}
    public static void main(String[] args){
        System.out.println(isAdmin("Admin"));
    }

    public static void main2(String[] args) {
        String s1 = new String("aaa xzasss");
        String s2 = new String("aaasss");

        String s3 = s1;
        System.out.println(s1 == s2);
        System.out.println(s1 == s3);
        System.out.println(s1.equals(s2));
        System.out.println(s1.equals(s3));
        System.out.println(s1.replace('a', 'j'));
    }
    public static void main1(String[] args) {
        String s1 = "aaasss";
        System.out.println(s1.replace('a','b'));
        System.out.println(s1);

    }
}